People with the same condition have different features, even
within the same family. Different organs can be affected and some
people may have mild symptoms while other people are severely
affected. These differences can happen because of other genes
or something in the environment.

Reduced penetrance

In some conditions, a person can carry the gene change that
causes the condition but have NO symptoms.

Patterns of Inheritance (e.g., What is my chance of having another
child with the condition? How is the condition passed on in the family?
Are my relatives at risk for having this condition or having children
with the condition?)

Educational and informational materials: Organizations that create
materials should have information about clinical experts. Contributing
authors are often experts on the conditions and may have additional
resources and contacts.

Use of support groups: Members of these groups may be able to identify
local providers and/or national experts and provide information about
their experiences with different doctors.

Approach to testing if multiple methods are available (e.g., biochemical
and genetic testing) or changes in multiple genes have been associated
with the condition.

Information about sensitivity (How often is the test positive, meaning
a mutation is present, when the condition is present?) and specificity
(How often is the test negative when the condition is not present?)

Interpretation of test results for diagnosis, management, and family
members—positive, negative, and variant of unknown significance.